On This Day, March 20, 1917, the modern all-purpose zipper is patented, by Gideon Sundback.
These days, zippers are so commonplace on clothing that we don’t really them–until they stop working. We routinely take them for granted. We zip them up and down many times daily without ever giving a second thought to who invented them, how complex they are, or how much of an innovation they were more than a century ago.
But today, take a look at a zipper on whatever you’re wearing. You’ll see the little teeth are lined up on two separate pieces of cloth tape. The slider device that unites the teeth has to move smoothly up and down, or side-to-side, and it requires a small but easy-to-use pull-tab. Once closed, the teeth need to provide a firm hold. Zippers also need a “stop” piece at both the top and the bottom of the zipper to keep a slider from running off its track.
The challenge of the earliest zippers was making ones that were reliable and that would lie flat. If the zipper buc
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